looking for info/tutorials on diy fishnet trampoline

[TwoBirds]

Hi All,

I'm making a small  ~4' x 8' trampoline from fish net and I'm looking for tutorials on tying the edge rope to the net, actually, since I've never worked with fish net before or made a trampoline I'm looking for any and all info I can find on either subject, any tips, tricks, or ideas are welcome.

Here's where I'm at



2b

 

[Zonker]

I used that style for my tramps.  I would roll up a few diamonds to give it extra bulk and anti-chafe abilities before lashings of 1/4" rope to the padeyes.  I tried to have 3 separate lashings along each edge, so if a single lashing failed you don't have a huge hole at the edge.

It can be very stretchy, so assume you will have to re-tension in a few weeks after installation.

 

[The Mad Hatter]

The nets on my tri are dyneema SK75 netting for the main nets and fishing net for the fwd nets as they are just there to stop sails from falling in the water.

On the main nets that take crew weight I just looped the netting over some 8mm rope and just weaved a couple rows of  3mm cord through the mesh to lock the netting.

So the lashing is boat to 8mm.  

I found the details on a web site that sold netting for this purpose  when I was building a few years back  but cant seem to find it again.

On the fwd nets I used the same method but with 4mm and 2mm in place of the 8 and 3.

It has worked well for me but I did have to re tension a couple of times. It now seems stable. I don't think I will have to re tension again.

However if I do it is pretty easy. Just pull the 3mm out , wrap the 8mm a couple squares   further into the net and rethread the 3mm.

Please see  the nets in the pic if my explanation is unclear.

 

[TwoBirds]

Thanks everybody, I'd have thought this would be a fairly common topic but info is really hard to find.

 

[nyker]

Indeed. I had a hard job of finding out how to do it as well. Couldn't find any info on the net either.

In the end I doubled the edges back. I knotted the doubled back edge with dyneema lashing thread. That was quite a job,  took me 160m of thread and a lot of time for the 6 nets. I then reefed a 10mm line through. I made sure I had some room for play , but I was still surprised by the amount of slack that has appeared after just a few days of sailing. Except for the outer edges of the main nets I knotted all attachments individualy.

 

[Table_Chairs]

For mine I doubled over the outer square of netting and then threaded rope through that doubled section. I then lashed it all together. It was pretty time consuming, but the result is good. Netting is knotless polyester.

 

[Russell Brown]

I used fiberglass tubing woven through the edges to make a stiff and straight border. It makes the loads even on the net and means far less lashing points.

 

[Table_Chairs]

You want to make sure it's slightly underside to allow for stretch. I thought mine would have much more clearance but when tensioned I was lucky there was just enough. 

 

[TwoBirds]

Thanks again everybody, I'm starting to get a handle on it

Because the boat has to come apart every time I use it I'll be putting the tramp in a wooden frame, I'm thinking of putting a bit of curve in them to make them stronger, just wondering if it's a good Idea or not?

The tramp will be supported on both long sides.

strips are spruce, 1 1/2" X ~15/16th" and the blocks are  1" thick by 1 1/2" wide cedar, I'll glue it up with west systems thickened with fumed silica, no screws, think it'll hold up? 



2b

 

[Mark Morwood]

I don't quite have a picture in my head of how you are trying to mount it, but if it needs to be removable have you considered sail track with slides?

 

[TwoBirds]

Sorry, I tend to ramble when posting about a project and then go back and edit, guess I took out too much.

I hadn't thought of sail tracks and slides but I am now, thanks.

I have to put the tramp in a permanent frame so I can flip it up to paddle between the hulls, should make assembly fast too.

the table is 4'x8', I put a bit of camber in the sides to keep them from collapsing from the tension.



Because the frame will be under tension all the time I decided to run a couple 3/8" dowels through each cedar block to stop the epoxy from creeping.

Just need to make the knees and epoxy them and the dowels in place and I can finish sanding and start varnishing.

I'm not sure if it'll hold up, guess I better where my wet suit the first few times I try it out .

I sure picked a good time to work on it, there hasn't been a breath of wind here in a week and the smoke from the fires down south is thick enough that I'm not up to paddling.

 

[23feet]

I have found the Sailrite 24oz - 30oz trampoline mesh to be very hard wearing (but not the 10oz). Something to consider if you want a cheaper/easier alternative.

 

[PIL66 - XL2]

[No message]

 

[TwoBirds]

Hi All

Finally got the netting stretched in the frame last night, I wanted to give the epoxy a full week to cure before I put any stress on it.

I tied it in on the corners and then used a few zip ties to center it before I started stretching it, I  wasn't able to source any fiberglass tubing locally, Had a look at schedule 40 pvc pipe but decided that it'd weight too much so I wove the edge rope through 3 meshes in from the edge and folded those 3 meshes over and then wove a second rope through to lock it down like Mad Hatter suggested, which leaves one more mesh which I'll leave till the netting is fully stretched and then either cut it off or lash it down.

I had some dowel left over so I pegged the plywood corner braces down as well, finished weight is 19 1/2 pounds, 7 pounds less than the old plywood seats it's replacing.

 

Thanks again for all your help

2b

 

[TwoBirds]

well, after a couple months of use it's held up well, it's comfy enough sitting or lying down, but if I have to kneel the knots are absolutely brutal on the knees, I'll be replacing it with something knotless, and sooner rather than later.

2b

 

[SSolo]

try spectra knotless netting it is far nicer, less stretch and stronger. For fitting I use the boat and ratchet straps  to apply the tension using a sail batten or similar as the stretcher

 

[cyclone]

My choice but not cheap. When I ordered a kit it included netting, thicker perimeter rope, thin dyneema for securing the perimeter with two rows of running clove hitch and a large spool of 1/8” dyneema for lashing to the boat. The knot-free is comfortable, strong, low stretch and has held up well.

http://www.net-sys.com/catamaran-netting/

 

[hump101]

I used fiberglass tubing woven through the edges to make a stiff and straight border. It makes the loads even on the net and means far less lashing points.

Mine are like this, but with solid fibreglass rod. Makes for an even, but heavy, job, and the rods have splintered in a few places, where the net and UV has attacked them.

 

[cyclone]

This is an example of the knot free. Simpler than the method I used.